PMA to Present on Early-Dates Bias in CPM Risk Analysis at AACE’s Annual Meeting



06/26/2016 to 06/29/2016




Sheraton Center – Toronto, ON, Canada



Conference information


Dr. Gui Ponce de Leon and Vivek Puri, will present on removing the early-dates bias in CPM Risk Analysis at the upcoming AACE’s 2016 Annual Meeting. The annual meeting is an excellent opportunity to network with your peers, earn CEUs/PDHs and attend the latest papers on cost, schedule and management.


(RISK-2196) Removing the Early-Dates Bias in CPM Risk Analysis

Primary Author: Dr Gui Ponce de Leon PE PMA Consultants, LLC
Co-Author(s): Dr Vivek Puri PMA Consultants, LLC
Time/Location: TUE 11:00-12:00/Room 5


The Critical Path Method (CPM) schedules activities to start on early dates, which results in an unrealistic completion distribution in CPM risk analysis. CPM risk analysis tools, thus, cannot model what commonly occurs when a project unfolds and activities start on dates later than early dates due to floating or pacing decisions based on schedule progress. Graphical Path Method (GPM®) risk analysis allows activities in each realization to float as a function of random sampling and decision rules, accurately modeling the real world where activities are delayed to take advantage of total float. This paper demonstrates how the early bias in CPM risk analysis leads to optimistic completion distributions, and how GPM risk analysis corrects for the early bias by allowing floating and pacing scenarios. A novel approach is also introduced for developing a bounding completion distribution envelope for selecting realistic probabilistic completion dates and for monitoring safe-float use as the project progresses.



Gui Ponce de Leon, PhD, PE, LEED AP, PMP

Gui Ponce de LeonDr. Gui is recognized as one of our nation’s foremost planning and scheduling subject matter experts. His broad professional experience includes executive and senior roles as investor’s developer, program manager, construction manager and EPC contractor planner/scheduler. Dr. Gui has continually pioneered innovations in project management throughout his 40-year career. He has written widely on the use of CPM in construction contracts as well as on schedule, delay, and acceleration analysis. His recent work with the Graphical Path Method (GPM®) is revolutionizing planning and scheduling at a level not seen since the advent of critical path methods.



Vivek Puri, PhD, PMP

Vivek PuriDr. Puri has expert experience in construction management research, simulation and risk management, and construction planning and execution. He completed his PhD in Civil Engineering (2012) from Purdue University and Master of Technology in Construction Technology and Management (2005) from Indian Institute of Technology Madras, India. Dr. Puri’s PhD thesis focused on combined continuous and discrete event simulation of project operations and its use in project planning.



Learn more about PMA’s Project Risk Management Services and GPM Risk Analysis.


Link to conference site